Among silver halide color photographic materials, those containing three kinds of color couplers which form yellow, magenta and cyan colors upon coupling with an oxidation product of an aromatic primary amine color developing agent, respectively are most conventional.
As the magenta coupler employed therein, pyrazolotriazole magenta couplers, for example, those as described in U.S. Pat. No. 3,725,067 are preferred from the standpoint of color reproduction because they form azomethine dyes which have a less undesirable subsidiary absorption in the region around 430 nm. Also, they are preferred since the occurrence of yellow stain in uncolored portions owing to heat and humidity is restrained.
However, these couplers have a problem in that the azomethine dyes formed therefrom have only low fastness to light.
In order to improve light-fastness of the pyrazoloazole type magenta couplers described above, various techniques has been proposed. For example, it is known to employ spiroindane type compounds as described, for example, in JP-A-59-118414 (the term "JP-A" as used herein means an "unexamined published Japanese patent application"), phenol or phenol ester type compounds as described, for example, in U.S. Pat. No. 4,588,679, JP-A-60-262159 corresponding to U.S. Pat. No. 4,735,893 and JP-A-61-282845, metal chelate compounds as described, for example, in JP-A-60-97353 corresponding to U.S. Pat. No. 4,590,153, silyl ether type compounds as described, for example, in JP-A-60-164743 corresponding to U.S. Pat. No. 4,559,297, and hydroxychroman type compounds as described, for example, in JP-A-61-177454. The light-fastness can be improved to some extent according to these techniques, but is still insufficient.
In accordance with hitherto known techniques including those described above, the effect for improving light-fastness of a dye image formed in areas of low density is small as compared to that in areas of high density, and as a result the color balance, particularly in the low density areas, of the three colors of yellow, magenta and cyan, of the remaining dye image, is changed. Thus, the effect for improvement is not satisfactory. Therefore, a technique for improving light-fastness of a dye image formed in the low density areas is desired.